The present invention relates to a novel article of manufacture, and more particularly to an accordion-pleated article which is particularly suitable for covering guide tracks and the like of machines, and for similar applications.
Such articles, which may be channel-shaped or tubular, are already known. In some instances the main material of which they are made, e.g. leather, asbestos, artificial leather, is stiffened and reinforced on its entire inwardly directed surface with a lining of synthetic plastic sheet material or the like. Experience has shown, however, that those dual-ply (or even multiple-ply) articles have certain drawbacks. In particular, the linings used do not meet the often very stringent requirements which are made in terms of mechanical strength and thermal resistance.
Other problems which have been encountered have to do with inadequate resistance of the lining materials to attack by water, oil and/or petroleum products, leading to a deterioration of the folding characteristics expected from the articles. Also, the lining material is folded where the pleats of the outer or main material are folded. Because the lining material is often quite stiff, this leads in some instances to a tendency of the article to lift off (bend away from) the guide track or the like which is to be protected. This latter problem can be overcome by incorporating wire guides in the pleats, which counteract this tendency; however, this is evidently not only expensive in terms of labor and additional material required, but it also leads to an often totally undesired increase in the weight of the article.